why?

B

Not only X, but also Y is the idiom in which X and Y are both used in the same light.

b) the lines have not only lowered pollution levels, but also helped in decongest

Shouldn't it be helped in decongesting ??

and Why did you guys eliminate D ??

I understand the problems with other choices but why eliminate D. ?

The answer comes down to B and E as they both follow the idiom "not only.....but also".

The error in B is that the "helped in decongest" phrase which should be helped in decongesting....!!!

E is the answer for me..!!!

All the options seem wrong to me.
B could have been correct in 'decongesting' was used.
What's the OA?

yup B would have been correct if decongesting would have been used..........in decongest is the wrong usage.......correct usage is to decongestin case if intention is to be shown.......

Oh boy, I just caught this now that you guys have mentioned it. E is the best remaining choice now as B 's decongest is incorrect.

voodoo_child wrote:The rapid-rail lines that were recently introduced in Sourthern California have had positive effects : not only have they lowered pollution levels, they have helped in decongesting the region's freeway system, which had been operating far above its capacity.

a) not only have they lowered pollution levels, they have helped in decongesting
b) the lines have not only lowered pollution levels, but also helped in decongest
c) not only have pollution levels been lowered, but they have helped to decongest
d) lines have lowered pollution levels, as well as helped in decongesting
e) not only have they lowered pollution levels, but also have they helped decongest

Please explain your answer...

We need to use the idiom NOT ONLY X BUT ALSO Y
so left with option B and E

b) the lines have not only lowered pollution levels, but also helped in decongest
lowered population level || helped in decongest

ALSO NOTE: we need to have the lines/THEY outside not only but also idiom for 2 reasons
1) Being inside it gets repeated and causes wordiness.
2) It is seperated by colon, and we have an independent clause after colon. SO it works as the subject of this independent clause.

In B, the decongest seems bit strange but still i ll go with it. IMO B

What's the OA?

Although i feel E is correct, but wordy.
Thanks

voodoo_child wrote:The rapid-rail lines that were recently introduced in Sourthern California have had positive effects : not only have they lowered pollution levels, they have helped in decongesting the region's freeway system, which had been operating far above its capacity.

a) not only have they lowered pollution levels, they have helped in decongesting
b) the lines have not only lowered pollution levels, but also helped in decongest
c) not only have pollution levels been lowered, but they have helped to decongest
d) lines have lowered pollution levels, as well as helped in decongesting
e) not only have they lowered pollution levels, but also have they helped decongest

Please explain your answer...

hello guys

eventho opE has a bit weird construction, but it is logical

btw whats the OA

regards nafi

OA is B. I am still not sure why E) is not correct

voodoo_child wrote:OA is B. I am still not sure why E) is not correct

Hi,
not only have they lowered pollution levels, but also have they helped decongest
This is very awkward construction.
As every option is incorrect, for E to be correct I think it should be:
not only have they lowered pollution levels, but also helped to decongest

IMO B